[uneasyrider]

Below is the combo, what kind of mileage do you think I'm getting on the highway? I just completed a 120 mile trip and I got a good check so I know what it's getting +1mpg. I kept my foot out of it except for one truck I had to pass and I stuffed my foot into it hard in 3rd. It had been hell the last 50miles or so of the trip being so mellow so I had an excuse to jump on it. I'll give you a hint, it's more then 15mpg.

E-heads (out of the box)

462cid (400 block 0.060 over)

Eagle crank and H-beam rods

10.2:1 compression

Pistons = SRP

RPM manifold

Crower part # 60243 Grind # 284HDP: (2,500-6,000)

@ 0.050 228/235

112deg lobe sep.

0.479/0.494 (w/1.5:1)

1.5:1 rockers

stock 800cfm Q-jet

Hooker Super Comp. headers (2" primary, 3.5" collector)

Kumho ECSTA MX 255/45 17's front and 285/40 17's rear "Y" speed rated 186 mph

Stock Super T-10 4-spd

Comp Engineering Subframe connectors

Comp Engineering Traction bars (to be installed soon)

10 bolt GM, 2.73 rear (soon to have a new Eaton posi)

[70 bird]

I guess 17?? Dont know but it sounds alot better than what I get!! lol

[quick67bird]

I am guessing 16.5 Uneasyrider. It is a heck of alot better than my 5mpg. Those low gears really hurt mileage. We need to hook up I will be getting my KRE heads this week and they flow 340 cfm. In October I am going to go to Yakima and spray the motor with the a 300 horse shot of NOS.

Robert

[larry davis]

13.5

[azbirds]

Well, You going to tell us.

[uneasyrider]

Originally Posted by quick67bird

I am guessing 16.5 Uneasyrider. It is a heck of alot better than my 5mpg. Those low gears really hurt mileage. We need to hook up I will be getting my KRE heads this week and they flow 340 cfm. In October I am going to go to Yakima and spray the motor with the a 300 horse shot of NOS.

Robert

Get this Rob! You know this route.

I filled up in Burbank at that Shell station on the right as you head to Wallula, drove through Walla Walla, over to Waitsburg, and back to W. Richland where I filled up at the Sun Mart station there in town, 4.081 gallons!

P.S. I bet people from out of town are going to love these city names. I also drove through Dixie (and it's South of me but I wouldn't say it was "Way down South..." LOL), Touchet (Where the old radio add said you could get Hiney Wine ) through Minnick, Buroker, and don't forget the major metropolis of Prescott. I had a friend that graduated from Prescott with the 6 other kids that graduated that year.

[quick67bird]

Originally Posted by uneasyrider

Get this Rob! You know this route.

I filled up in Burbank at that Shell station on the right as you head to Wallula, drove through Walla Walla, over to Waitsburg, and back to W. Richland where I filled up at the Sun Mart station there in town, 4.081 gallons!

P.S. I bet people from out of town are going to love these city names. I also drove through Dixie (and it's South of me but I wouldn't say it was "Way down South..." LOL), Touchet (Where the old radio add said you could get Hiney Wine ) through Minnick, Buroker, and don't forget the major metropolis of Prescott. I had a friend that graduated from Prescott with the 6 other kids that graduated that year.

That was a bit of a drive. I know those areas well I delivered freight out that way. Some nice curves from Dixie to Waitsburg for some corner carving.

[uneasyrider]

Originally Posted by quick67bird

That was a bit of a drive. I know those areas well I delivered freight out that way. Some nice curves from Dixie to Waitsburg for some corner carving.

YES, YES IT IS. I had friends that grew up there and we would go stay up in Waitsburg on holidays. Those roads are what drove me to build this car. If there were work up there I would live there. I love the Dayton/Waitsburg area. We drove like MAD men around there when we were kids. Our friends had a foreign exchange student that lived with them from Japan. His perants had LOTS of money and it was VERY strange to have this kid there in the "Waitsburg setting". For his HIGH SCHOOL graduation present back in 1982 he got a Lotus Esprit (non turbo lol) and it cost $45,000 back then! That was a go cart! Man it would corner good. That was quite a site to see in Waitsburg.

[b-man]

The only way you're going to get an accurate assesment of your fuel mileage would be to fill the tank all the way up at your favorite station. Fill it until the pump shuts off, then go to the next $.25 or so. Record the mileage on your odometer.

Then drive enough to use up a good portion of the tankful, not just 4 gallons. Then return to your favorite station and fill up again using the same exact technique at the SAME pump. This way your car is on the same exact level ground in the same exact spot it was on before. This will greatly affect the way the tank fills. Being on a different level at a different station might cause the car to take one less gallon at one station compared to another. Record the number of gallons and the mileage.

Only then can you calculate a somewhat accurate fuel mileage number. Going to different gas stations and getting only about 4 gallons with an inaccurate odometer won't get you a number that's 'real-world'.

Using the method above (same pump, same station, accurate odometer) and repeating it on about 5 to 10 fill-ups will give you a good number.

Now please try again. No way did your car get 28 MPG.

[Brandi Kay]

ya, you gona tell us?

[Formulafr]

i think 16mpg


i made 16,6 with my small 350

[uneasyrider]

YOU GUYS ARE GOING TO CRAP! I'll tell you and I'm going to get a bunch of "No freecking ways!" and all I can tell you is that my brother rode with me and he was there when I filled it... 28mpg!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! NS! 28mpg! I got 17mpg one day when I checked it after nailing it hard several times before I checked. NO JOKE! And it will do ludacris speed on top of that.

P.S.!!!!!!!!!!!!!!!!!!!!!!!!!!!!! I say it got 28mpg ONLY because I give a bit of error BUT (GET THIS) I only put EXACTLY 4.081gal. of gas in it. LOL!!!!!!!!!!!!!!!!!!!!!! NS!!!!!!!!!
The speed'o is off so my odometer isn't correct so I got the milage two ways. I went on line to a site that will calculate the miles between cities AND I got out the map and the dividers and did it the old fashioned way and came up within about 10miles difference so I averaged them.

[BVR421]

Originally Posted by uneasyrider

The speed'o is off so my odometer isn't correct so I got the milage two ways. I went on line to a site that will calculate the miles between cities AND I got out the map and the dividers and did it the old fashioned way and came up within about 10miles difference so I averaged them.

nice try but no dice, maps calculate city to city beween zip codes and post offices
never the less you are obviously getting great mileage which indicates a great job on the tuneup

[Steve C.]

I figured that the next time I cruise out to meet Witchdoctor for lunch, mostly open highway at 65 mph or so and thru a few small towns, it will cost me about $55 for the 150 mile trip. This based on $3.00 per gallon pump gas.

But damn, worth every penny of it

[elohssa]

Hey, My car is sort of similarily specced I built it for corner carving also and I just took it on a long road trip through the mountains best I got was 19mpg. It's got a 455, t-10 4spd 3:08 gears,fairly mild cam (forget specs) holley street avenger 770cfm carb, 1969 stock intake, and slightly built/ported 4x heads that have been milled 0.40 The gas prices just about killed me on this trip but I can't bear to park it (It's just too fun to drive). Next year it's getting fuel injection and a TKO 500, That should bump it up to the mid 20's I hope. Heres a pic taken in British Columbia

[uneasyrider]

Originally Posted by elohssa

Hey, My car is sort of similarily specced I built it for corner carving also and I just took it on a long road trip through the mountains best I got was 19mpg. It's got a 455, t-10 4spd 3:08 gears,fairly mild cam (forget specs) holley street avenger 770cfm carb, 1969 stock intake, and slightly built/ported 4x heads that have been milled 0.40 The gas prices just about killed me on this trip but I can't bear to park it (It's just too fun to drive). Next year it's getting fuel injection and a TKO 500, That should bump it up to the mid 20's I hope. Heres a pic taken in British Columbia

Nice ride! Yep, it's similar to my set up and all I can tell you is that even if I wasn't getting the milage it looks like I'm getting I wouldn't be able to let it set long either. Cliff or Tom or a couple others might be able to tell me where I'm going "wrong" with my milage calc. if I am because I know they have had a BUNCH of experience with Q-jets and different set-ups. All I can tell you is that I think a lot of people that check there max. milage might be doing the old "Mr. Owl" check, "One, Two, Three... CRUNCH (the foot goes to the floor)." I was ONLY on the primaries other than the one pass and possably pulling out on the highway once where I might have cracked the secondaries.

[uneasyrider]

Here is an example of a VERY heavy car that didn't get that bad of mileage if you compare it to a "car" the same weight today like an SUV. This is out of an old test drive artical from 1957:

"Salesmen and others paid expenses on a per-mile basis should find it especially valuable! Speaking of gas mileage, the Cadillac turned in averages just about on a par with other cars in its class. City driving under varied traffic conditions resulted in an 11 mpg average. Highway cruising average was about 16-17 mpg at steady speeds of 50-65 mph. Overall average was just under 14 mpg."

The average 1957 Caddy weighed in at 4,600lbs curb weight and had a siginficantly larger frontal area and Cd than my TA. Here is another from a book I have "Encyclopedia of American Cars 1930-1980":

"The 1963 models would reach 115-120 mph, do 0-60 mph in 10 seconds and 0-80 mph in 16 seconds, and would return about 14 miles per gallon."

The average 1963 Caddy weighed in at 4,600lbs curb weight also and still had a MUCH greater frontal area and Cd than my TA.

The average 1974 TA weighed in at 3,700lbs curb weight. You knock 1000lbs off a car and cut the Cd from approx. 0.5 to 0.4 and the frontal area from say 30sqft to 24sqft (all total SWAG's) that will make a big difference in fuel milage. Then change from a automatic tranny to a manual. The gearing for both cars is more than likely on par. I don't know if the new Q-jets are "better" carbs than the older Caddy carb but there is another possable gain. Just some food for thought. I have also seen on other posts on here that there are people getting quite good mileage (20mpg+) with there big Pontiacs.

An old Motor Trend for a 1965 GTO:

"In the same ad referred to above, Pontiac also hints that the GTO is a gas hog. Actually, you can drive it to deliver some remarkably good gas mileages when you consider its weight and the brute power on tap. Our low mileage figure of 11 mpg came in stop-and-go driving, when we used this spirited car's performance to the hilt. We were so surprised when we got 19 mpg on a 200-mile trip of steady 65-70-mph freeway driving that we rechecked it with another 100-mile drive (this one included secondary roads and small towns), and backed it up with 17.6 mpg. Our average for the entire test was 13.2 mpg."

I'm thinking if that GTO was getting 19mpg with the 3.23:1 diff., 2spd power slip, same curb weight, and 4bbl carb. I think I can beat it with 2.73's and a 4-spd manual.

[4004spdta]

Getting good gas mileage in a Trans Am....hmmm. Not being a smart ass but if your worried about gas mileage in your old Pontiac, maybe you should sell it and by a Honda. Guys that can afford to buy Vipers, Corvettes, V10 SRT 10 Trucks, Ford Lightning trucks, Trans ams, GTO's, Z28's, SC Mustangs, don't worry about gas mileage. If they worry about gas mileage then they can't afford the car. I had a guy the other day ask me what kind of gas mileage does my TA get. My reply was " who cares, I don't".
Bottom line is I really don't care what it gets. Its a toy to me.

[Reed179]

Well said 4004spdta, 8mpg or 28mpg doesn't matter,gonna drive it anyway!

[Reed179]

28mpg?? Would love to know how you could have possibly managed that! Would also like to know how you got 462ci out of a .060 over 400! I had an all stock 78 T/A with the same gears and got maybe 16mpg at best, I wouldn't change the first thing on that car if it's cranking out 28mpg!!